1. Field of the Invention
This invention relates generally to electrical power distribution apparatus and more particularly to a combination service entrance device having an elevated removable load center that provides space for routing wires between the enclosure and the load center and further provides more efficient air circulation in the load center section compared to the prior art devices.
2. Description of the Related Art
Combination service entrance devices having a common enclosure for housing a utility meter socket, and a load center or panel board having one or more service disconnects and a plurality of branch circuit breakers have been gaining commercial use, particularly for use in residential dwellings. The term "combination" refers to the fact that the unit encloses both the mounting provisions for a utility-company watt-hour meter ("meter") and a panel board containing circuit breakers for the distribution, control and protection of various circuits in a building.
Utility companies require that utility meter section of any such combination service entrance device be separated and sealed from the "customer's" side, i.e., the circuit breakers. Therefore, the manufacturers of such devices place a solid barrier at or near the center of the common enclosure to provide two sections or compartments: one sealed compartment for housing the meter socket and the other an unsealed compartment for housing the panel board. In order to provide access to the meter by the utility companies, the combination service entrance devices are usually installed on the outside.
In prior art devices, the panel board, which contains one or more service disconnects and a plurality of branch circuit breakers, is usually placed near the back panel of the common enclosure, which leaves a large empty space between the panel board and a cover or door placed on the panel board section. Electrical conductors carrying main power from the meter socket are routed across the wire way, which obstructs the load wiring and requires routing of the load wires either over or under the line side main power connectors, which always are electrically live. Wires and cables connected between the circuit breakers and their respective loads are placed around the panel board.
In many applications the electrician connecting the circuit breakers in the combination unit to the various loads must pull a large quantity of wires within and through the load center where the main service enters the building and the branch circuit breakers are distributed. When a large number of wires must be pulled, the load center interior installed at the back of the panel board section of the combination device inhibits routing of such wires. It also forces the electrician to route some of the wires over electrically live connectors. Although such connectors are insulated, it is more desirable to run all wires away from any live connectors.
The lack of wiring space, especially behind the panel board, exposes the panel board components to potential damage. Also, technicians installing the service sometimes suffer cuts and bruises on their hands. Since the panel board is installed on the back of the panel board section of the common enclosure, all the wires must be routed around the interior and all the space above the panel board is wasted. Also, some technicians prefer to first remove the panel board from the enclosure, pull wires into the enclosure and then install the panel board when they are ready to make connections to the circuit breakers. However, the panel boards in the currently available combination service entrance devices are difficult to remove and re-install.
Accordingly, a need exists for a combination service entrance device which more efficiently utilizes the space within the panel board section of the enclosure, provides more space for routing the wires underneath the panel board, is configured to provide relatively easier routing of wires in the panel board section and in which the panel board may be easily removed and re-installed in the field.
The present invention addresses the above-noted deficiencies of the prior art combination service entrance units and provides an improved combination service entrance device which more efficiently utilizes the space within the panel board section of the enclosure, provides more space for routing the wires and is configured to provide relatively easier routing of wires in the panel board section and enables electricians to relatively easily remove and re-install the panel board in the field.